docs: def add_subproject(self, fname, conf_path):
          """Creates and adds a new subproject."""
          config = Config(conf_file=conf_path)
          proj = Project(self.app,
                         dependency_map=self.dependency_map)
          proj.parse_name_from_config(config)
          proj.parse_config(config)
          proj.setup()
          self.subprojects[fname] = proj